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By making the simulation gradually more accurate it was proved that for decreasing the temperature at the point of damper in the unaffected tunnel tube, it is necessary to build a fire-resistant partition EW 180 in the airway and to direct thus the flow of hot combustion gases straight into the chimney of the ventilation building (see Figure 1b).
This fire model of the field type [10], [11] is based on the computational method CFD that makes it possible to model the dynamics of flow of hot gases and combustion gases.
Fires with outputs in a range from 8 to 200 MW and duration in a range from 45 to 100 minutes (see Figure 2) represent fires, from passenger car collision fire to the extreme case of petrol tanker fire; these outputs were chosen for simulation owing to the expected large volume of goods traffic.
Fig. 2 Fire scenarios (heat release rate) suitable for fire modelling using the CFD technique [13] For simulation, a flow velocity of 1 m/s in the tunnel, representing the variant of ventilation at the fire during bi-directional traffic in the affected tunnel tube, was used.
Determination of the heat release rate inside operational road tunnels by comparison with CFD calculations.

Aspect ratio (b/a) a (m) b (m) Dh (m) Circular - - 0.12 - square - 0.12 - Rectangular 0.1632 0.096 0.12 1.7 0.24 0.08 0.12 3 elliptic 0.17 0.1 0.12 1.7 0.09 0.27 0.12 3 2.2 Mathematical equations The Navier-Stokes equations of the turbulent flow are solved using, k-ω SST turbulent model provided by ANSYS CFX-CFD code.
[5] Wahba, E.M., Steady flow simulations inside a driven cavity up to Reynolds number 35,000, Computers & Fluids, vol. 66, pp. 85-97, 2012
M., Bessaïh, R., Numerical simulation of natural convection heat transfer of copper-water nanofluid in a vertical cylindrical annulus with heat sources, Thermophysics and Aeromechanics, vol. 26, pp. 325–334, 2019
[21] Ahlman, D., Brethouwer, G., and Johansson, A.V., Direct numerical simulation of a plane turbulent wall-jet including scalar mixing, J.
[22] Iftekhar, Z., Tucker, G., and Yan, L., Large-eddy simulation of the interaction of wall jets with external stream, Int.

To guarantee the design requirement, this paper uses the methods of Computational Fluid Dynamics (CFD) technology and field test to optimize and modify the original design of the cavity’s structure.
This paper uses the CFD software PHOENICS(2006) to simulate the air flow in the competition hall and the air flow characteristic in the structure cavity.
Sketch of computational area Numerical Simulation Method The turbulence model used in the numerical model is the widely used standard model.
Numerical Simulation of Air Distribution of Chair Ventilation on Theaters.

Aerodynamics Research of Thermal Fluid Circulation in a Heated Cavity Guang Zhao1,a 1Aircraft Dynamic Department, Aviation University of Air Force, Changchun 130022, China alixuezhaoguang@126.com Keywords: numerical simulation, natural convection, lattice Boltzmann method, bottom heating.
In this paper, numerical simulation of natural convection in a closure square cavity with heating source on the basement is carried out using thermal lattice Boltzmann method.
Although there are a few literatures on this problem, including experiments and simulations [2, 3], most of them are focused on the location of the heating source or the nonlinear characteristics under different Rayleigh number .
Results for the simulations of range from 0.1 to 1.0, and varies from 103 to 106 are obtained.
Okui: Mathmatics and Computers in Simulation, Vol. 72-2(2006), p.195-200.

Our previous researches on this topic fundamentally used contemporary numerical methods (such as CFD (computational fluid dynamics), MD (molecular dynamics), etc.) to study the ultra-filtration properties and made several progresses.
And the further application of this parallel scheme could form a new concept of MD simulation.
In the MD simulation works[7, 8], molecule models (such as H2O, Al2O3) are simply recognized as balls.
Apparently, parallel computation schemes should be applied to such a complicated bio-chemical simulation system to improve the computation performance.
Tang, in: The theories and applications of molecular simulation.

In fact, their experimental validation showed that the theoretical simulation was in close agreement with the experimental results.
Then, Theodosius et al. [14] presented an experimental-numeric comparison to give the precision of the CFD model.
In the present paper, a numerical simulation and experimental validation in our SAH test bench are developed.
Indeed, we have built numerical simulations to characterize the aero-thermal structure of our new system operating in natural convection.
Teodosiu, CFD modeling of buoyancy driven cavities with internal heat source: Application to heated rooms, En.

From the ANSYS CFX® 15.1 software, the geometry (Fig. 1) and the mesh (Fig. 2), more precisely the ICEM CFD 15.1 software were constructed.
The Mesh of the 8-hole hollow brick used in the simulation.
The h value is calculated from the results of numerical simulations.
Experimental parameters of air and ceramic brick [2] and properties used in the simulation.
Silva: Simulation and Experimentation of the Drying of Ceramic Bricks.

A representative numerical method is Finite Element Method (FEM), which has been widely applied in the field of Computational Fluid Dynamics (CFD) [4].
Numerical Simulation using the Particle Method SPH.
In our simulation, impact simulation is conducted using the ANSYS®AUTODYN® software, which is able to reproduce phenomena induced by impacts, high pressure, or explosions.
Fig. 8 shows the long-term simulation result after impact on the sand (0–15 ms).
In contrast, the sand was ejected upward and spread gradually in the simulation.

VIV of the cylindrical structure at subcritical Reynolds number (Re) of 3.8 x 104 is studied using a RANSE based CFD transient fluid structure interaction dynamic simulation model employing a user defined function for modeling the response.
The two dimensional (2D) VIV simulations are carried out using RANSE based CFD method.
From the numerical simulations and the subsequent analysis the average flow and motion parameters are as reported in Table 2.
At the investigated mass ratio, a hybrid mode of vortex shedding is observed from the numerical simulations.
Three-dimensional numerical simulation of two-degree-of-freedom VIV of a circular cylinder with varying natural frequency ratios at Re= 500.

And the CFD simulation analysis of the model with the testing parameters is taken.
And the simulation model adopts the 0.5 MPa air-pressure, 150 ℃bitumen temperature and 8% cold water ratio.
The analysis of foamed bitumen outlet flow control laws Based on the bitumen foaming model and the test data of the simulation, Fig. 5, Fig. 6 and Fig. 7 list the simulation results of the different spout sizes.
The paper adopts the simulation data of following graphs and data fitting curves.